The FBI admitted just days after the Florida shooting that it failed to pass the tip along to its Miami field office for further investigation.

No one at the bureau has been fired or reprimanded over the incident yet.

A top FBI official told lawmakers on Wednesday that it's still unclear how the agency fumbled a tip warning that 19-year-old Nikolas Cruz was about to “explode” and could shoot up a school.

David Bowdich, the FBI's acting deputy director, testified before the Senate Judiciary Committee about the agency's response to the tip and the changes the bureau has implemented to prevent a similar incident.

The FBI admitted just days after the Florida shooting, which left 17 people dead, that it failed to investigate a tip it received in January from an unidentified woman who spoke with an FBI call-taker based out of West Virginia.

According to FBI protocols, the call-taker should have forwarded the tip to the agency's Miami field office for further investigation. But Bowdich said Wednesday that after the call-taker consulted with her supervisor, they closed the case.

When Sen. Lindsey Graham of South Carolina asked Bowdich what made the supervisor believe that the tip shouldn't be passed along to the field office, Bowdich said it's unclear.

“The way the call was presented between the call taker to her supervisor — we have two different recollections,” Bowdich said. “So we do not actually know what was presented. So in the future, one of the recommendations is there will be more fidelity on how that was presented, and more of a thorough review.”

No one at the FBI has been reprimanded or fired — yet

Several of the lawmakers appeared frustrated or confused at times during Bowdich's testimony about the FBI's handling of the fallout.

Sen. Ted Cruz of Texas appeared baffled during Bowdich's testimony about the lack of consequences the FBI employees faced.

“Has anyone been held accountable? Has anyone been reprimanded? Has anyone been terminated?” he asked Bowdich.

“As of today, no,” Bowdich responded.

Sen. John Kennedy of Louisiana noted that months have now lapsed since the FBI first received the tip on January 5.

“Do any of you know what happened to that person who didn't do his or her job?” he said. “I don't mean to denigrate anybody. … Do we know who did it and whether there were consequences?”

Bowdich responded that the issue was “more of an internal agency matter.”

He also told the lawmakers that the FBI is evaluating whether employees' training and performance metrics played a role in the tip failure. He noted that training for the agency's call-takers used to be a three-week session that they expanded to eight weeks.

Bowdich added that the agency used to judge the call-takers' performance based on how quickly they took tipsters' calls, and how long it took them to follow-up with database checks.

“We're not so sure that we didn't potentially drive some behavior there that is not good in a case like this,” he said. “Certainly you have to hold people accountable for their time while they're on the line, but that's something we've asked our inspection team to look carefully at.”

Bowdich also told the senators that the FBI has launched two separate investigations into the Cruz case — one involving the tip to the West Virginia call center, and another involving an earlier tip from a YouTube user who reported that a user named “Nikolas Cruz” had left a comment on his video saying he wanted to be a “professional school shooter.”

Bowdich said FBI investigators in the second case interviewed that tipster and conducted “open-source checks” to figure out the identity of the user.

But the investigators, who came across a similar lead from their Houston office, found that the term “school shooter” was being used as a joke on social media. They then “washed that lead out,” according to Bowdich.